We design routing and scheduling policies that optimize network throughput in multi-hop wireless networks where nodes are powered by renewable energy sources. The policies that we propose deliver maximum throughput, and yet do not require explicit knowledge of the statistics of the energy harvesting or the traffic generation processes. We consider both the cases of infinite and finite energy storage capacity at nodes. The results in the latter case provide bounds on the capacity of the energy storage devices at the individual nodes that is minimally required for obtaining maximum throughput.